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We describe a new map-making code for cosmic microwave background (CMB) observations. It implements fast algorithms for convolution and transpose convolution of two functions on the sphere (Wandelt & G\'{o}rski 2001). Our code can account…

Astrophysics · Physics 2009-11-10 Charmaine Armitage , Benjamin D. Wandelt

A previous work (Monteser\'in et al. 2008) estimated the CMB variance from the three-year WMAP data, finding a lower value than expected from Gaussian simulations using the WMAP best-fit cosmological model. We repeat the analysis on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. Cruz , P. Vielva , E. Martínez-González , R. B. Barreiro

Multiply connected space sections of the universe on a scale smaller than the horizon size can leave an imprint on cosmic microwave background polarization maps, in such a way that the so-called ``circles-in-the-sky'' method can be used to…

We extend the previously described CMB Gibbs sampling framework to allow for exact Bayesian analysis of anisotropic universe models, and apply this method to the 5-year WMAP temperature observations. This involves adding support for…

Astrophysics · Physics 2011-02-11 Nicolaas E. Groeneboom , Hans Kristian Eriksen

Recent observations have pointed out various anomalies in some multipoles (small $\ell $) of the cosmic microwave background (CMB). In this paper, it is proved that some of these anomalies could be explained in the framework of a modified…

Astrophysics · Physics 2009-11-13 J. A. Morales , D. Sáez

We study the angular distribution of temperature fluctuations in the cosmic microwave background (CMB) to probe the statistical isotropy of the universe by using precise full-sky CMB data with a model-independent approach. We investigated…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-01 C. E. Kester , A. Bernui , W. S. Hipólito-Ricaldi

Several unexpected features are observed at large angular scales in the CMB temperature anisotropy measurements by both WMAP and Planck. These include the lack of both variance and correlation, alignment of the lowest multipole moments with…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-25 Jessica Muir , Saroj Adhikari , Dragan Huterer

Conformal cyclic cosmology (CCC) posits the existence of an aeon preceding our Big Bang 'B', whose conformal infinity 'I' is identified, conformally, with 'B', now regarded as a spacelike 3-surface. Black-hole encounters, within bound…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-18 V. G. Gurzadyan , R. Penrose

We explore the low-l likelihood of the angular spectrum C(l) of masked CMB temperature maps using an adaptive importance sampler. We find that, in spite of a partial sky coverage, the likelihood distribution of each C(l) closely follows an…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 K. Benabed , J. -F. Cardoso , S. Prunet , E. Hivon

Unexpected features have been observed in the cosmic microwave background (CMB) temperature on large scales. We revisit these CMB anomalies using new foreground-cleaned CMB temperature maps derived in a companion paper from WMAP and Planck…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-05 Laura Herold , Graeme E. Addison , Charles L. Bennett , Hayley C. Nofi , J. L. Weiland

Recent observations suggest that there are violations of the isotropy of the universe at large scales, an important part of the cosmological principle. In this paper, we use the Cosmic Microwave Background (CMB) data to search for spatial…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Shek Yeung , Ming-Chung Chu

Large patterns could exist on the microwave sky as a result of various non-standard possibilities for the large-scale Universe -- rotation or shear, non-trivial topology, and single topological defects are specific examples. All-sky (or…

Astrophysics · Physics 2009-10-31 Emory F. Bunn , Douglas Scott

Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

Astrophysics · Physics 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

We examine all-sky cosmic microwave background (CMB) temperature maps on large angular scales to compare their consistency with two scenarios: the standard inflationary quantum picture, and a distribution constrained to have a universal…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-13 Nathaniel Selub , Frederick Wehlen , Craig Hogan , Stephan S. Meyer

The motion of our solar system relative to the CMB rest frame leads to subtle distortions in the observed CMB sky map due to the aberration effect. Usually the corresponding peculiar velocity is determined from the CMB dipole but neglecting…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-30 Ralf Aurich , David Reinhardt

The presence of matter in the path of relic photons causes distortions in the angular pattern of the cosmic microwave background (CMB) temperature fluctuations, modifying their properties in a slight but measurable way. Recently, the Planck…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-11 G. A. Marques , C. P. Novaes , A. Bernui , I. S. Ferreira

It has been recently realized (Rephaeli 1995) that the relativistic corrections to the spectral distortions of the cosmic microwave background (CMB) measured in the direction of clusters of galaxies containing hot gas are significant and…

Astrophysics · Physics 2007-05-23 S. Y. Sazonov , R. A. Sunyaev

Recent observations have indicated a Cosmic Microwave Background (CMB) temperature decrement in the direction of local galaxies within the 2MASS Redshift Survey. We investigate this detection by analyzing its frequency dependence and…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-06 M. Cruz , E. Martínez-González , C. Gimeno-Amo , B. J. Kavanagh , M. Tucci

We use an optimal estimator to study the variance of the WMAP 9 CMB field at low resolution, in both temperature and polarization. Employing realistic Monte Carlo simulation, we find statistically significant deviations from the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 A. Gruppuso , P. Natoli , F. Paci , F. Finelli , D. Molinari , A. De Rosa , N. Mandolesi

Significant alignment and signed-intensity anomalies of local features of the cosmic microwave background (CMB) are detected on the three-year WMAP data, through a decomposition of the signal with steerable wavelets on the sphere. Firstly,…

Astrophysics · Physics 2009-09-29 P. Vielva , Y. Wiaux , E. Martinez-Gonzalez , P. Vandergheynst